feat: 集成 Battle tab 到 BuddyPanel，重命名 data/ 为 dex/ 规避 gitignore

- BuddyPanel 新增 Battle tab，BattleFlow 加 isActive 控制
- BattleFlow configSelect 阶段支持 ↑↓ 选择物种
- packages/pokemon/src/data/ → dex/，解决根 .gitignore 匹配问题
- 全量 Tab→2空格 缩进转换

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

packages/pokemon/src/dex/xpTable.ts

@@ -0,0 +1,81 @@
+import type { GrowthRate } from '../types'
+
+/**
+ * Calculate total XP required to reach a given level for a growth rate type.
+ * Follows original Pokémon XP curve formulas.
+ */
+export function xpForLevel(level: number, growthRate: GrowthRate): number {
+  if (level <= 1) return 0
+  const n = level
+  switch (growthRate) {
+    case 'erratic':
+      return xpErratic(n)
+    case 'fast':
+      return Math.floor((n * n * n * 4) / 5)
+    case 'medium-fast':
+      return n * n * n
+    case 'medium-slow':
+      return Math.floor((6 / 5) * n * n * n - 15 * n * n + 100 * n - 140)
+    case 'slow':
+      return Math.floor((5 * n * n * n) / 4)
+    case 'fluctuating':
+      return xpFluctuating(n)
+    default:
+      return n * n * n
+  }
+}
+
+/**
+ * Calculate level from total XP for a given growth rate.
+ */
+export function levelFromXp(totalXp: number, growthRate: GrowthRate): number {
+  // Binary search for level
+  let lo = 1
+  let hi = 100
+  while (lo < hi) {
+    const mid = Math.ceil((lo + hi) / 2)
+    if (xpForLevel(mid, growthRate) <= totalXp) {
+      lo = mid
+    } else {
+      hi = mid - 1
+    }
+  }
+  return Math.min(lo, 100)
+}
+
+/**
+ * XP needed to go from current level to next level.
+ */
+export function xpToNextLevel(currentLevel: number, totalXp: number, growthRate: GrowthRate): number {
+  if (currentLevel >= 100) return 0
+  const nextLevelXp = xpForLevel(currentLevel + 1, growthRate)
+  return nextLevelXp - totalXp
+}
+
+// Erratic growth rate (complex piecewise)
+function xpErratic(n: number): number {
+  if (n <= 1) return 0
+  if (n <= 50) {
+    return Math.floor((n * n * n * (100 - n)) / 50)
+  }
+  if (n <= 68) {
+    return Math.floor((n * n * n * (150 - n)) / 100)
+  }
+  if (n <= 98) {
+    return Math.floor((n * n * n * Math.floor((1911 - 10 * n) / 3)) / 500)
+  }
+  // n 99-100
+  return Math.floor((n * n * n * (160 - n)) / 100)
+}
+
+// Fluctuating growth rate (complex piecewise)
+function xpFluctuating(n: number): number {
+  if (n <= 1) return 0
+  if (n <= 15) {
+    return Math.floor((n * n * n * (Math.floor((n + 1) / 3) + 24)) / 50)
+  }
+  if (n <= 36) {
+    return Math.floor((n * n * n * (n + 14)) / 50)
+  }
+  return Math.floor((n * n * n * (Math.floor(n / 2) + 32)) / 50)
+}